Backport of UI Hide Secrets Sync from nav if not on license and/or no policy permissions into release/1.17.x

[hc-github-team-secure-vault-core]

Backport

This PR is auto-generated from #27262 to be assessed for backporting due to the inclusion of the label backport/1.17.x.

The below text is copied from the body of the original PR.

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Adding Do not merge label so this is target for 1.17.1 and does not get into GA.

• ent test pass

This PR hides Secrets Sync from the sidebar navigation under the following circumstances. The decisions was made to remove the upsell badges because showing Secrets Sync to users who do not have this feature or have the feature but do not have any access to the sys/sync endpoint is an anti-pattern to how the UI currently handles showing/hiding features.

Notes:

• I do not do any type of redirect or navigation prevention if a user manually finds the Secrets Sync page.
• I do very little to client counts: I change the name of a getter and use the same flag service getter to show or hide the link to Secrets Sync overview.
• I do not address the situation where a user—with policy permissions—still cannot activate Secrets Sync from within a namespace. That will be addressed in another PR and targeted for 1.17.1.
• The permissions paths I gathered from scanning through the sync api.

These changes do the following:

1. Hides Secrets Sync nav from all OSS users.
   

2. Displays only one upsell badge for HVD managed clusters. We cannot tell which tier they are on. In the future this will likely change.
   

3. If you're an Enterprise user without Secrets Sync on your license, you will not see it in the sidebar nav.
   

4. If you're an Enterprise user with Secrets Sync on your license and it's NOT activated, you will see the sidebar nav (regardless of your policy permissions).

# user bob with the following policy
path "sys/sync/*" {
  capabilities = [ "deny" ]
}

path "sys/activation-flags/secrets-sync/*" {
  capabilities = [ "deny" ]
}

7. If you're an Enterprise user with Secrets Sync on your license and it IS activated, you will only see Secrets Sync if you have access to sys/sync endpoints.

Below is a user Bob with the ability to read on sys/sync/destinations only, and he can see it.

Below is a user Maria with the default policy (no access to sys/sync), she can not see it.

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Overview of commits

• 927da85

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CI Results:
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